GENERAL BIOLOGY 2

• Reproduction


  The biological process in which offspring are produced from their parent or parents
• Sexual reproduction

  • Use of sex cells (gametes)
  • Involves the fusion of male and female gametes to form zygote
  • Genetic variability
• Asexual reproduction


  • Does not involve gametes, instead parts of a mature organisms may develop to new individuals
  • Offspring in genetically identical to the parent
• Binary fission


  1. Separation of the body into two new bodies

  2. Common in single-celled organisms
• Budding


  1. A new organism develops from an outgrowth from the parent body known as bud

  2. Once grown, the new organism detaches from the parent body
• Fragmentation


  The parents' body breaks into several pieces where each piece grows into a new individual
• Vegetative reproduction


  A plant part such as stems, leaves, roots or turions are used to reproduce new plants
• Male reproductive system


  • The penis is the male organ for sexual intercourse and urination
  • The scrotum is a loose, pouch-like sack of skin that covers the testicles and hangs behind the penis
  • The testes is the site of testosterone production
  • Seminiferous tubules are the coiled collection of tubes within the testicles where spermatogenesis takes place
• Female reproductive system


  • The uterus hosts the fetus that is developing
  • The ovaries produce the anatomically female eggs and also produce and secrete progesterone and estrogen
• Oogenesis


  1. The process of formation of the ovum

  2. The process occurs in the ovaries of the female

  3. One oogonium produces a single ovum

  4. Primary oocyte is the diploid cell, which is divided by meiosis, forming a single ovum

  5. Oogenic germ cells are called oogonia, which are stem cells, self renewing and differentiating into ova
• Spermatogenesis


  1. The process of the formation of haploid sperms from a diploid stem cell known as spermatogonium

  2. The process occurs inside the seminiferous tubules in the testis

  3. The entire process takes about 70 days

  4. Spermatogenic germ cells are called spermatogonia

  5. Spermatogonia are stem cells that are capable of self-renewing

  6. They differentiate into intermediate spermatogonium, which is committed to differentiating into spermatozoa
• Fertilization


  1. Sperm and egg unites in one fallopian tube to form a zygote

  2. The zygote will travel down the fallopian tube, where it becomes a morula

  3. Once the morula reaches uterus, it'll become blastocyst

  4. Blastocyst burrows into the uterine lining – a process called implantation
• Gastrulation


  An early developmental process in which an embryo transforms from a one dimensional layer of epithelial cells (blastula) and reorganizes into a multilayered and multidimensional structure called the gastrula
• Ectoderm

  • Epidermis of skin and its derivatives (including hairs, sweat, hair follicles)
  • Epithelial lining of mouth and anus
  • Cornea and lens of eye
  • Nervous system
  • Sensory receptors in epidermis
  • Adrenal medulla
  • Tooth enamel
  • Epithelium of pineal and pituitary glands
• Mesoderm

  • Notochord
  • Skeletal system
  • Muscular system
  • Muscular layer of stomach and intestine
  • Excretory system
  • Circulatory and lymphatic system
  • Reproductive system (except germ cells)
  • Dermis of skin
  • Lining of body cavity
  • Adrenal Cortex
• Endoderm

  • Epithelial lining of digestive tract and respiratory system
  • Lining of urethra, urinary bladder, and reproductive system
  • Liver
  • Pancreas
  • Thymus
  • Thyroid and parathyroid glands
• The fetal stage of development begins around the ninth week and lasts until birth. This is when the embryo officially turns into a fetus.
• Carpel/Pistil


  Female portion of a flower. Stigma - sticky; to trap pollen, Style - hollow tube which connects stigma and ovary, Ovary - produces female gametes (ovules)
• Male gametophyte


  1. Inside the anthers' microsporangia, male gametophytes divide by meiosis to generate haploid microspores which, in turn, undergo mitosis and give rise to pollen grains

  2. Pollen grain contain two cells: one generative cell and cell that will become the pollen tube cell
• Female gametophyte


  1. The ovule inside the ovary contains the megasporangium

  2. Within each megasporangium, a megasporocyte undergoes meiosis, generating four megaspores; three small and one large
• Pollination


  The transfer of pollen from an anther to a receptive stigma. Agents: animals, wind, water, humans
• Fertilization


  1. One sperm and egg combine, forming a diploid zygote, the future embryo

  2. Double fertilization - other sperm fuses with 2n polar nuclei, forming a triploid cell that will develop into the endosperm, which is the tissue that serves as a food reserve
• Embryo development


  1. Ovules become the seed

  2. Ovary matures into the fruit
• Seed germination


  Germination is the resumption of growth and development after a period of seed dormancy
• Nutrition


  Nutrients help living organism develop their bodies, grow, heal damaged body parts, and give energy for life and activity
• Modes of nutrition


  • Autotrophic - Can produce their own food
  • Heterotrophic - Cannot produce their own food
• Digestion


  The mechanical and chemical process by which complex food substances are broken down into simpler substances
• Digestive system


  • Mouth
  • Esophagus
  • Stomach
  • Liver
  • Gallbladder
  • Pancreas
  • Small intestine
  • Large intestine
  • Anus
• Digestive process

  1. Ingestion - taking in food materials

  2. Digestion - breaking down food into smaller pieces

  3. Absorption - movement of nutrients, water and electrolytes from the small intestines into the cell, then into the blood

  4. Elimination - undigested material passes out of the system
• Feeding mechanism of animals

  • Substrate-Feeders
  • Filter-Feeders
  • Fluid-Feeders
  • Bulk-Feeders
• Required nutrients

  • Carbohydrates
  • Fats
  • Proteins
• Essential nutrients

  • Amino Acids
  • Fatty Acids
  • Vitamins
  • Minerals
• Photosynthesis


  The process by which light energy is converted to chemical energy for plants to make their own food
• Plant parts involved in photosynthesis

  • Roots - absorbs and transports water and nutrients from the soil to the rest of the plants
  • Leaves - the part of the plants where photosynthesis takes place. Chloroplast contains chlorophyll that traps sunlight. Exchange of oxygen and carbon dioxide happens inside the stomata
• Feeding mechanism of carnivorous plants

  • Pitcher Plant - gives sweet odor to make their prey fall into the pitcher
  • Venus Flytrap - Closes down and traps their prey when touched
  • Cobra Lily - Confuses their prey when they enter its translucent window in the leaf
  • Yellow Pitcher Plant - Collects rainwater to attract their prey
  • Sundew - Traps its prey using its sticky substance found in their leaves
  • Monkey Cup - Traps and feed on their prey inside their cups
• Circulatory system of animals


  • Functions: Circulate blood throughout the entire body, Transport of oxygen to cells, Transport of carbon dioxide away from cells, Movement of immune system components, Transport of endocrine gland
  • Types: Open circulatory system - the blood flows freely through the cavities since there are no vessels to conduct the blood, Close circulatory system - the blood flows through the arteries and veins connected by capillaries
• Open Circulatory System


  • The blood flows freely through the cavities since there are no vessels to conduct the blood
• Close Circulatory System


  • The blood flows through the arteries and veins connected by capillaries
• Simple organism


  • Organisms which have a two-cell layer covering get their supply of gasses and excrete wastes through DIFFUSION
• Chambers of the heart

  • Right Atrium
  • Right Ventricle
  • Left Atrium
  • Left Ventricle